New Ultrathin Flat Lens Technology Could Lead to Credit Card Thin Smartphones
Posted on October 1, 2012
Applied physicists at the Harvard School of Engineering and Applied Sciences (SEAS) have created an ultrathin flat lens that focuses light without imparting the distortions of conventional lenses. Astigmatism and coma aberrations do not occur with the flat lens. The lens is just 60 nanometers thick. 1,500 of the lenses would fit across the width of a human hair. The technology could lead to smartphones as thin as a credit card. The technology was reported in the American Chemical Society's journal Nano Letters.
The surface of the lens is patterned with tiny metallic stripes which bend light differently as one moves away from the center. This causes the beam to sharply focus without distorting the images. The developers say their flat lens eliminates optical aberrations such as the fish-eye effect that results from conventional wide-angle lenses.
Principal investigator Federico Capasso said in a statement, "Our flat lens opens up a new type of technology. We're presenting a new way of making lenses. Instead of creating phase delays as light propagates through the thickness of the material, you can create an instantaneous phase shift right at the surface of the lens. It's extremely exciting."